Final answer:
A. Light and darkness. The contrast that Lord Byron employs in his poem 'She Walks In Beauty' is light and darkness.
Step-by-step explanation:
The contrast that Lord Byron employs in his poem 'She Walks In Beauty' is A. Light and darkness.
This can be seen in the following lines of the poem:
'She walks in beauty, like the night
Of cloudless climes and starry skies.'
These lines illustrate the contrast between darkness (night) and light (cloudless climes and starry skies). Lord Byron uses this contrast to describe the beauty and grace of the woman he is writing about.